Mold for casting metals



- Oct. 1, 1929. GUYOT 1,729,643

MOLD FOR CASTING METALS Original Filed April 15, 1925 7%W 1 B a;

Patented Oct. 1, 1929 UNITED STATES PATENT OFFICE MARIUS GUYOT, OF CLEVELAND, OHIO, ASSIGNOR TO ALUMINUM COMPANY OF AMERICA, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA MOLD FOR CASTING METALS Original application filed April 13, 1925, Serial No. 22,590. Divided and this application filed August 4,

1926. Serial This invention relates to casting articles from molten metal or metallic alloy, and it is more particularly directed to the construction of the gate through-which the molten metal flows into the mold cavities and the relation of the gate to the mold cavities.

An object of this invention is to provide an improved gate which will render the production of castings uniform, expeditious and economical.

Other objects will hereinafter appear.

The invention will better be understood from the description of one practical embodiment thereof which is illustrated in the accompanying drawings, in which Fig. 1 is a longitudinal, central, sectional view of a permanent mold provided with my improved gate;

Fig. 2 is a plan view of the mold partly 29 shown in section taken on the line 2-2 of Fig. 1; and

Fig 3 is an elevation of the castings and gate as taken from the mold illustrated in Figs. 1 and 2.

This application is a division of my copending application Serial No. 22,590, filed April 13, 1925 now Patent No. 1,679,860, August 7, 1928.

The mold illustrated herein consists of a mold base 1, a bottom member 2 and a top member 3. The bottom and top members are secured together by means of bolts 4. The top member is provided with two openings 5 through each of which projects a pilot 6 which is capable of limited movement therein. The lower end of the pilot 6 rests on the top surface of the bottom member and has an outstanding shoulder or flange 6 to retain it in place. The top surface of the pilot is preferably larger than the casting cavity of which it forms one end wall. Through the center of the pilot a hole -7 is provided which, when fitted with a plug 8 having a serrated outer surface, is adapted 35 to permit the escape of air from the casting cavity as the molten metal enters. The depression formed above the plug provides a boss which may be utilized in machining the casting.

At one end of the mold base an upstanding hinge pin 9 is provided which is attached to the base by a nut 10 clamping the base between the nut and a shoulder 11 formed on the pin. Hinged to this pin are two mold halves 12 and 13 which are provided upon their ends opposite the pin 9 with a locking bar 14 cooperating with cap screw 15 by which they may be locked together. The lower surfaces of the mold halves are cut away to receive the parts of the pilot 6 which project above the top surface of the member 3. The mold halves, however, closely engage the pilots when locked together and align the pilots with respect to the other walls of the casting cavity at the various temperatures occurring during the casting operation.

The adjacent faces of the mold halves 12 and 13 are suitably recessed to provide a gate, riser, and casting cavities therebe-t-ween,

there being in the mold herein illustrated two casting cavities 16, each provided with a main riser or feeder cavity 17 and an auxiliary riser or feeder cavity 18. The auxiliary risers are located between the respective casting cavities and the adjacent ends of the mold halves, while the main riser cavities are positioned between the casting cavities. A compound gate serves to conduct molten metal simultaneously into the adjacent riser cavities 17 and the casting cavities 16. Briefly it comprises a common inlet passage 19, discharge necks 20 communicating with the feeder cavities, these being in communication with the casting cavities through narrow passages 21. The discharge necks extend upwardly and outwardly from the lower end of the inlet as shown and then curve upon themselves and converge downwardly curving again to diverge outwardly to meet the feeder cavities. It will thus be seen that the lower end of the inlet and the end of the discharge necks communicativ therewith form a liquid seal, when molten metal is introduced into the inlet,and that the seal together with the curves followed by the discharge necks prevent the metal from entering the mold in a broken or agitated stream which might result in defective castings.

Theriser cavities communicate with the halves to provide cored out wrist pin bosses walls ofcasting cavities for internal combustion engine pistons, and are located and supported by engagement of the flanges 26 with the upper edges of the mold halves. Core pins 27 project through the sides of the mold on the piston castings. A mechanism for inserting and withdrawing these pins is indicated generally at 28, and as this mechanism is fully-described in the present application it will not be described in detail herein.

\Vhile I have described my invention as inlet, and the connecting passages to each cavity enter the inlet at a point below the top thereof so as to form an hydraulic seal around the juncture of all said passages with the inlet.

' I do not, therefore, limit myself tothe precise details shown herein but claim as my invention all modifications coming within the scope of the subjoined claims.

What is claimed is:

1. In a permanent mold for making two piston castings simultaneously, the combination of a mold base and two mold halves, the adjacent faces of the mold halves being cut away to form gate, riser, and casting cavities for two piston castings, the gate cavity comprising a single inlet passage and two passages disposed between the casting cavities, each passage leading into a riser adjacent to and in communication with a castingcavity.

2. In a permanent. mold having mold halves provided with two cavities, a gate comprising a downwardly extending inlet passage and two upwardly diverging control diverging in a wide curve and opening into riser cavities through vertically extended openings.

4. In a mold carrying a plurality of casting cavities, a gate comprising an upright inlet passage, a plurality of upright feeders each communicating with a casting cavity through a narrow upwardly extending opening, and liquid-seal forming passages connecting the inlet passage with the feeders.

5. Ina permanent mold having two casting cavities, a gate comprising an upright inlet passage, an upright feeder closely adj acent to each casting cavity and communicating therewith through a short, narrow passage extending for substantially the full height of said cavity, and smoothly curving passages of decreasing cross-sectional area communicating with the inlet passage and the feeders for conducting molten metal through a liquid seal at the inlet passage, to the feeders and casting cavities, smoothly and without substantial agitation.

6. In a permanent mold having a plurality of mold cavities, a gate comprising an inlet, diverging connecting passages extending therefrom forming a hydraulic seal at the lower end of the inlet, feeders with which the outer ends of said passages communicate, each feeder communicating with one mold cavity, and risers in communication with each of said mold cavities.

7. In a mold, two mold halves pivotally connected together at one end and provided ,with a plurality of casting cavities and provided with a gate between the casting cavities, the gate comprising a single inlet passage, a

plurality of upright feeders, each communicating with a casting cavity thru a narrow inlet opening, and passages connecting the passages which bend upon themselves to con-' verge downwardly and then diverge downwardly in wide sweeping curves, each control passage opening into a riser adjacent to and in communication with one casting cavity.

3. A permanent mold having two casting c vities, each provided with a riser cavity adjacent thereto and communicating therewith throughout the majority of its height,

'a gate comprising a downwardly extending sages bending downwardly back on themselvesto converge downwardly and finally 

